HISTORICAL CHANGES OE FAUNA. 
Moll. 35 
Historical Changes op Fauna. 
The lake of Ossegor, Dept. Landes, 600-700 metres from the sea, and 
formerly fresh with a slight admixture of brackish water, has been 
invaded by an irruption of the sea, the freshwater animals being sud- 
denly destroyed and a new marine fauna growing up. Folin, “ Fauno 
lacustre de I’ancien lac d’Ossegor” ; J. de Conch, xxv. pp. 183 & 184. 
Several instances of southern species of land shells extending their 
range gradually towards the environs of Lyons are pointed out by A. 
Locard, Ann. Soc. Agric. Lyon (4) x. [1877] pp. 93-116. 
Dreissena polymorpha (Pallas) made its appearance in the side canal of 
the Garonne in September, 1863 ; Gassies, Bull. Soc. L. Bord. 1878, & 
J. de Conch, xxvii. p. 374. 
Successful introduction of Helix villosa (Dr.) from Switzerland to 
Durham, of Parmacella near Newcastle, and of H. lapicida from the 
south of England on the banks of the Wear, but vain attempts to accli- 
matize African and Syrian Clausilice and Helices at Durham, by H. B. 
Tristram, Zool. (3) i. [1877] p. 260. 
Helix liinbata (Drap.) acclimatized for some years in the woods of 
Meudon and Clamart, near Paris ; II. pisana (Miill.) at Charenton, near 
Paris, since 1870 ; and II. virgata (Dacosta) = variahilis (Drap.), at 
St. Denis, Crenelle, and other localities on the borders of channels and 
railways : Jousseaume, Bull. Soc. Z. Fr. iii. [1878] pp. 33, 217, & 214. 
Pupa umhilicata (Drap.) introduced about Gape Town ; Gibbons, J. 
of Conch, ii. p. 282. 
Helix aspersa (Miill.), costata (Mull.), similaris (Fer.), and [^Ilyalina'] 
cellaria (Miill.), and Bulimus acutus (Miill.), acclimatized in several 
localities of Australia, the second {jmlchella) also at Norfolk Island, 
cellaria in New Zealand; Petterd, Mon. of Tasm. Land Shells (not seen 
by the Recorder), & J. of Conch, ii. pp. 96 & 97 ; Legrand & Nelson, 
tom. cit. pp. 95, 281, & 282. 
Planorhis lacustris (Mont.) and Limnwa stagnalis (L.) introduced into 
Australia ; Petterd, 1. c. p. 97. 
Limncea peregra (Miill.), and probably also stagnalis (L.), in Tasmania; 
Nelson & Legrand, 1. c. pp. 4 & 95. Eggs probably introduced with 
fish-eggs; Petterd, 1. c. p. 81. 
Helix cellaria (Miill.) found in a greenhouse at Detroit, Michigan, not 
before known in the country ; Walker, tom. cit. p. 327. 
Bulimus decollatus (L.) and Helix lactea (Miill.) are introduced in 
Cuba ; Arango y Molina, Faun. mal. Cubana, p, 131. 
Unio ruhiginosus (Lea) and gihhosus (Barnes), western species, intro- 
duced to the east by the Erie Canal, also U. pressus (Lea) found in New 
• York State; P. E. Call, Am. Nat, xiii [1878] pp, 472 & 473. 
Supposed recent extinction of Cyclostoma elegans in North Herts ; 
H. G. Fordham, P. Watford Soc. i. [1877] pp. 172, 173, & 187 (J. of 
Conch, ii. p. 297). 
